Photovoltaic thermal (PVT) collector

ABSTRACT

A solar cell and water heater plate assembly is disclosed which may be incorporated into a PVT collector.

RELATED APPLICATIONS

This application claims priority under 35 U.S.C. §119 to, Thailand Patent Application No. 0601003308, entitled Photovoltaic Thermal (PVT) Collector and filed on Jul. 14, 2006, the disclosure of which is expressly incorporated be reference herein.

FIELD OF THE INVENTION

The present invention relates to the solar cells, and in particular to the production of hot water and electricity.

BACKGROUND OF THE INVENTION

The conventional PVT collectors use amorphous silicon PV (photovoltaic) module with the top layer made of glass acting as light receptor. When sunlight travels to the PV module, some of the solar energy will be converted into heat and transmitted to the solar radiation plate, at the same size of the PV module, attached under the PV module by using thermally conductive epoxy. Heat will then be transmitted to the water running in the copper pipe under the solar radiation plate to generate hot water. The electricity produced is converted from direct current into alternate current for immediate direct connection to the existing power distribution system. Such a system has been disclosed in the application for the Thai Patent No. 058163 by the National Science and Technology Development Agency on “Amorphous silicon PVT collector” which is the use of amorphous type solar cell film attached directly to the heat receptor plate for transmission of heat to the hot water pipe so that the hot water can be used for various applications.

At a later stage, there was an attempt to improve the PVT collector and the installation method i.e. publication of application for patent of Japan JP 7 169 986 “SEALING METHOD OF AMORPHOUS SOLAR CELL” with the objectives of reducing cost for installation of the amorphous silicon PV module by providing the PV module with glass plate having amorphous solar cell one side, put on top with EVA (ethylene-vinyl acetate) plate for installation on the supporting plate. The whole assembly will then be put through lamination process using roller with heat at approx. 70° C. to eliminate air bubbles and to soften the EVA plate. After that, the assembly will be treated with heat at 130° C. and 5 bars of pressure for approximately 1 hour and then let it cool down at room temperature. However, installation of the copper pipe for hot water production to the supporting plate is still an awkward process.

Publication of the application for patent of Japan JP 2000241030 “SOLAR HEAT THERMOELECTRIC CONVERTION WATER HEATER PANEL” with the objectives of having simple installation of PVT collector by combining solar cell plate and the heat conductive copper pipe plate for the hot water production system from solar energy into one unit within the same frame for easier installation. However, leakage of water may be experienced after a period of operation leading to short circuit of the electrical system.

Publication of the application for patent of Japan JP 58-095147 “MANUFACTURE OF SOLAR HEAT COLLECTING UNIT” shows installation of copper tube with heat collecting aluminum plate by pressure welding directly to the aluminum plate according to the process in the Publication of the application for patent of Japan JP 57-041838 “MANUFACTURE OF ALUMINUM PANEL CONTAINING COPPER TUBE” which shows method of installation of copper pipe to the heat collecting aluminum plate by making a ring-shape from rolling aluminum strip and wrap it around copper pipe, and then weld the supporting legs together before attaching it to the heat conductive aluminum plate. There is the need for welding during installation of such invention which is a complicated process and time consuming.

The above invention, although it produces the required hot water and electricity, has the disadvantage in the way the components are connected to each other in layers with epoxy or welding causing heat loss. There is also the concern on the cost of the bonding materials. This has limited the real application of this equipment. Besides, its installation is still rather complicated and thus expensive.

Therefore, there is still the need to develop a PVT collector that is easy to install with a low installation cost.

SUMMARY OF THE INVENTION

The objectives of this invention is to develop the high efficiency PVT collector that can efficiently use solar energy and easy to install at a low installation cost.

In an exemplary embodiment of the present invention, the PVT collector includes a solar cell plate, and the water heater set consisting of an amount of amorphous silicon solar cell installed on the base plate made of glass for generating electricity from solar energy. There is also a layer of transparent polymer such as EVA (Ethylene Vinyl Acetate) which acts as a glue for bonding the glass and the solar cell to the metal plate used for collecting heat from the sun light for water heating purpose. The solar cell side of such metal plate is coated with transparent electrical insulator such as Unithane, a polyurethane, to prevent short circuit, while on the other side of the metal plate is layer of transparent polymer such as EVA (Ethylene Vinyl Acetate) used for fixing such metal plate to the pipe fasteners made of metal with a number of locking mechanisms in a semicircle shape perpendicular to such fasteners for fixing the copper pipe by clamping the copper pipe with the metal plate. Once water runs through the copper pipe, solar heat will be transferred to the water which will be stored in a hot water tank for further use.

In a further exemplary embodiment of the present invention, the PV module assembly as described above may be attached to a 3-layer aluminum frame. The top layer is the space for installation of the glass plate to create the green house effect. The middle layer of the frame is for installation of the solar cell plate and the water heater unit. The lower layer is the place for heat insulator. All are fixed within the aluminum frame with holes on the side of the frame for water pipe entering and exiting from the frame as well as for electrical wires.

In yet a further exemplary embodiment of the present invention, a PVT collector includes a number of amorphous silicon solar cells installed on a base plate made of glass for generating electricity from solar energy. Further, the PVT collector may include a layer of transparent polymer such as EVA (Ethylene Vinyl Acetate) to bond the glass and the solar cell to a metal plate that is collecting heat from solar energy for producing hot water. A side of the metal plate which is attached to the solar cell is coated with layer of electrical insulator which is transparent such as Unithane to prevent from short circuit. The other side of the metal plate is coated with a layer of transparent polymer such as EVA (Ethylene Vinyl Acetate) for securing such metal plate with a locking plate made of metal. The locking plate including a number of pipe locking parts of semicircle shape, perpendicular to the locking plate for securing a copper pipe to the metal plate. In one example, the copper pipe is coupled to the locking plate by means of clamping the copper pipe. As water runs through the copper pipe, heat will be transferred from solar energy to the water for further use. In one example, the above water heater and electricity generating assembly will be installed in a frame of which the top side is installed with glass to create green house effect and the bottom side is installed with heat insulator.

In yet another exemplary embodiment of the present invention, a solar cell and water heater assembly for coupling to a pipe with a fluid is provided. The solar cell and water heater assembly comprises a transparent plate used as base plate; a solar cell secured to the transparent plate; and a heat collecting metal plate that is made of heat conductive metal coated with an electrical insulator. The electrical insulator configured to protect from short circuit and corrosion. The solar cell and water heater assembly further comprises a first layer of polymer glue which attaches the transparent plate and the heat collecting metal plate; a fastening plate which includes a clamping means for holding the pipe, the fastening plate being made of a heat-conductive material; and a second layer of polymer glue which attaches the combination of the heat collecting plate and the electrical insulator to the fastening plate so that solar heat can be transferred to the fluid in the heat conductive pipe.

In still a further exemplary embodiment of the present invention, a PVT collector is provided. The PVT collector comprises an installation frame having a top, a middle, and a bottom portion; a light receptor glass plate installed on the top portion of the installation frame to create a green house effect; a solar cell and water heater plate assembly installed at the middle portion of the frame, the solar cell and water heater plate assembly configured to convert solar energy into electrical and heat energy; a heat insulator installed at the bottom portion of the frame; and a cover plate secured to the bottom portion to seal against moisture. The solar cell and water heater plate assembly includes a transparent plate used as base plate; a solar cell secured to the transparent plate; and a heat collecting metal plate that is made of heat conductive metal coated with an electrical insulator. The electrical insulator configured to protect from short circuit and corrosion. The solar cell and water heater assembly further including a first layer of polymer glue which attaches the transparent plate and the heat collecting metal plate; a fastening plate which includes a clamping means for holding the pipe, the fastening plate being made of a heat-conductive material; and a second layer of polymer glue which attaches the combination of the heat collecting plate and the electrical insulator to the fastening plate so that solar heat can be transferred to the fluid in the heat conductive pipe.

In still yet a further exemplary embodiment of the present invention, a PVT collector is provided. The PVT collector comprises a frame; a fluid carrying conduit passing from an exterior of the frame into an interior of the frame and again to the exterior of the frame; and a solar cell and water heater plate assembly coupled to the frame. The solar cell and water heater plate assembly includes a transparent base plate; a solar cell secured to the transparent base plate; a heat collecting plate positioned proximate the solar cell; a first layer of a polymer securing material which attaches the transparent base plate and the heat collecting metal plate; a fastening plate which includes a first portion that engages the fluid carrying conduit within the interior of the frame couple the fluid carrying conduit to the fastening plate; and a second layer of polymer securing material which attaches the heat collecting plate to the fastening plate so that during operation solar heat is transferred from the heat collecting plate to a fluid in the fluid carrying conduit.

Additional features of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of the presently perceived best mode of carrying out the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description of the drawings particularly refers to the accompanying figures in which:

FIG. 1: Cross-section drawings of each layer of the solar cell and water heater plate assembly according to this invention.

FIG. 2: The copper pipe fasteners according to this invention.

FIG. 3: Frame for fixing solar cell and water heater plate assembly in FIG. 1 together to build the PVT collector according to this invention.

FIG. 4: Framing process of all components according to this invention.

FIG. 5: All components of the PVT collector according to this invention.

FIG. 6: PVT collector according to this invention.

Corresponding reference characters indicate corresponding parts throughout the several views. Although the drawings represent embodiments of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present invention. The exemplifications set out herein illustrate embodiments of the invention in several forms and such exemplification is not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE DRAWINGS

Description of this invention is conducted by pointing out an example of the invention to be referred to by using the figures for illustration. The same parts or components in these figures shall be represented by the same reference numbers, without implication of limitation. The scope of the invention shall be in accordance with the claims attached. The embodiments discussed below are not intended to be exhaustive or limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may utilize their teachings.

FIG. 1 illustrates a cross-section of each layer of a solar cell and water heater pipe assembly according to an embodiment of this invention, which is part of the PVT collector.

According to FIG. 1, the solar cell and water heater plate assembly 10 includes clear glass 12 which is used as base plate for securing a solar cell 14 which should be of amorphous silicon type due to its stable functionality at high temperature. However, other types of solar cell may also be used. A first layer of polymer glue 15 is made of EVA (Ethylene Vinyl Acetate), for example, for fixing the clear glass plate 12 to a heat collecting metal plate 17 which is made of heat-conductive metal such as zinc, iron, copper, aluminum, etc. The metal plate 17 should be best coated with an electrical insulator 16 to prevent short circuit and corrosion caused by condensation of moisture in the atmosphere. Exemplary electrical insulator 16 include Unitane, a polyurethane. The insulator-coated metal 16,17 shall be fastened to the pipe fasteners 20 with a second layer of polymer glue 18. The pipe fasteners 20 for fastening the heat transfer pipe (see pipe 43 in FIG. 4) to the insulator-coated heat collecting metal plate 16,17 transfers heat from the sun light to the water in the heat transfer pipe 43. Details of the illustrated pipe fasteners 20 are shown in FIG. 2 to be further described.

FIG. 2 illustrates layout of one embodiment of water heater pipe fasteners.

The illustrated pipe fastener 20 is a metal plate of good heat conduction such as copper, aluminum, zinc-coated iron, etc. In one embodiment, it is of rectangular shape with a length of approximately 180 mm. and a width of approximately 125 mm. Size of the pipe fastener 20 may be changed as appropriate. In one embodiment, each pipe fastener 20 consists of means for securing 21,22 such as the edge end 22 and notched niche 21 which, in one embodiment, will generally be as long as the plate. The edge end 22 shall be perfectly fit within the notched niche 21 for proper engagement between the adjacent pipe fasteners 20. In one embodiment, the fastener plate 20 shall consist of means for clamping or parts for fixing with the pipe 23 or the securing rail at least one piece installed at approximately the middle of the plate. For better solution, such parts for fixing to the pipe shall have maximum contact with the fastener plate for maximum transfer of heat from the fastener plate to the pipe and the heat-carrying fluid within the pipe. It may be made in “S” shape for example. But, however, this could cause a more complicated installation as it may require bending of the heat-conducting pipe to the same shape of the parts fixing to the pipe 23. In one embodiment, the pipe fixing parts 23 may be of straight rail shape with the “U” or semicircle shape cross-section, and perpendicular to the plane of the plate. In one embodiment, width of the pipe fixing part 23 is generally around 0.5 inches so that it can be fixed with the heat-conductive copper pipe with 0.5 inches in diameter. In one embodiment, the pipe-fixing part 23 shall be as long as the fastener plate 20 for installation of the heat-conductive pipe by clamping into such “U” shape rail. In one embodiment, the pipe-fixing part 23 should be made of metal which might be welded to the plate 20. In other embodiments, the pipe-fixing part 23 is fastened with screw, or is an aluminum plate cast to be together with the metal plate in one piece.

In one embodiment, two fastener plates 20 are installed by putting them next to each other with the long sides of the plates in parallel. Then the edge end 22 of the first fastener plate 20 is inserted into the notched niche 21 of the second fastener plate 20 and engaged together. This is repeated with further plates 20 until the required size is reached.

Assembling of the Solar Cell and Water Heater Plate Assembly

Solar cell and water heater plate assembly 10 is a part of this PVT collector. In one embodiment, the solar cell and water heater plate assembly 10 is assembled by connecting all light receptors into one piece consisting of PV module 14 which is installed on the glass plate 12, adding a first layer of polymer glue EVA 15 and an electrical insulator to form an insulator-coated metal plate 16,17 (Unitane in one embodiment), adding a second layer of polymer glue EVA 18, and adding pipe fastener 20 with assembling of each component shown in FIG. 1. In one embodiment, the layers of EVA 15,18 shall bond the various components of each layer together by heat pressurized process or lamination because of melting EVA at 250° C. will act like glue pressed with pressure caused by the vacuum inside.

PV module 14, in one embodiment, is PV module of amorphous silicon type (in one embodiment, general size of around 635×1.245 mm.) assembled to a glass structure 12. In one embodiment, the back side is in a box shape with a terminal box at the middle and a bit to the top (not illustrated)

The metal plate 17 is coated with an electrical insulator 16, in one embodiment Unitane, to prevent short circuit and corrosion.

The pipe fastener plate 20 as shown in FIG. 2 is for fastening a pipe. In one embodiment, the pipe fastener 20 has a length of approximately 180 mm., a width of approximately 125 mm. In one embodiment, pipe fastener 20 is comprised of multiple sections or pieces that are attached together. In one embodiment, wherein the pipe fastener 20 has a length of approximately 180 mm and a width of approximately 125 mm a total of 30 pieces are used. It should be understood, that for pipe fastener 20 the size and number of pieces may be changed as appropriate to allow sufficient span for size of the main heat conductive pipe and the frame. There is also a hole for installing a terminal box which is used to help prevent moisture or humidity. The edge of the copper splice lock shall be filed to avoid damage to the seal (in one embodiment, a rubber plate such as a fluoroelastomer, such as VITRON a registered trademark of Dupont Dow Elasomers which is heat resistance up to 400° F./200° C. and resistance to fuel and chemical is used) in the process of creating vacuum as described below and to prevent damaging of various components, such as fasteners, in the laminator ovens.

In one embodiment, the splice plate for fixing pipe 20 is a flat metal plate with “U” or semicircle shape piece in the middle, perpendicular to the plate, for holding the pipe by clamping. In one embodiment, one end of the splice edge 20 is the niche 21 and the other end is the prominent part 22 perfectly fit with the niche of the other splice plate for fixing pipe.

FIG. 3 illustrates an embodiment of a frame for holding solar cell and water heater plate assembly 10 together to build the PVT collector.

FIG. 4 illustrates a framing process of all components.

FIG. 6 illustrates an embodiment of the PVT collector.

In FIG. 3, frame 30 consists of a first space 32, a second space 34, a third space 36, and a fourth space 38, respectively. In one embodiment, the first space 32 has the size adjusted for installation of clear glass to create the green house effect inside.

The second space 34 is the space for installation of PV module and water heater plate 10. The third space 36 is for installation of splice for fixing pipe 20 and the heat conductive pipe. Before installation, the rubber seal such as Buthyl Rubber should be attached to the edge of the solar cell and water heater plate assembly 10 which is to be placed in the second space 34 and the glass which is to be placed in the first space 32 on all 4 sides before the framing process to avoid moisture (see FIG. 4). The third space includes the rough skin polymer sheet. The fourth space 38 is the space for heat insulation for improving heating efficiency.

Preparation of the Solar Cell and Water Heater Plate Assembly 10

In one embodiment, after preparation of the work piece, lamination treatment process shall be started as follows:

-   -   1. Arrange the layout structure before laminating process by         arranging as per FIG. 1.     -   2. Put on rough skin polymer sheet and then put Viton rubber         plate on top of the rough skin polymer sheet.     -   3. Put the solar cell and water heater plate assembly in 4         trays, 2 trays at the top and 2 trays at the bottom. The trays         support the solar cell and water heater plate assembly.     -   4. Create vacuum in the tray ready with the work by switching on         the vacuum connected to the tray. The tray includes a small hole         adapted to bring the contents of the tray in communication with         the vacuum being applied.     -   5. Check whether there is air leakage at the solar cell and         water heater plate assembly.     -   If there is, check the rough skin polymer sheet to see whether         it gets in the way of the vacuum system and check the Viton         rubber to see whether it perfectly adhere to the o-ring.     -   If there is no leakage, proceed on to the next step.     -   6. Check to ensure that the vacuum is at approx 2-4 Torr.     -   7. Once the required vacuum is achieved, push the tray shelf         trolley into a laminator oven.     -   8. Before the heat treatment process, set timer of the oven         heater at 22 minutes and set timer for the circulating fan of         the oven at 27 minutes.     -   9. Switch on all 3 heaters and set temperature at 250 C and         switch on the circulating fan and exhaust fan.     -   10. Start the heat treatment until the heater timer has expired         and switch off all 3 heaters.     -   11. Wait until the timer for the circulating fan has expired and         then switch off the circulating fan.     -   12. After that open the oven, wait for 5 minutes while keeping         the exhaust fan operating until temperature in the oven is close         to the room temperature.     -   13. Pull the tray shelf trolley out of the oven. Let the work         cool down naturally.     -   14. Switch off the vacuum pump and take out the work tray.     -   15. Inspect the work piece for defects.

After the lamination process, put the solar cell and water heater plate assembly 10 in the frame 30 (as shown in FIG. 4 and 5) and install the glass as follows:

-   -   1. On the side of the frame 30 (in one embodiment with 1.245         meter length), measure and drill holes for main copper pipe on         all 4 sides and stick the copper pipe into the frame 30. Then         connect the header copper pipe 42 with the copper tubes 43 by         welding. In one embodiment, the connection is done by welding         before installing the copper pipe to the locking splice 20 to         avoid damage to the glass due to heat.     -   2. Attach Buthyl Rubber at the edge of PV module and edge of the         glass on all 4 sides before the framing process.     -   3. Install PV module and glass into the frame 30 on the length         side first. Then put the copper pipe to the locking splice of         the copper pipe, and then start framing process on the width         side, arrange the layout position of the frame and fasten with         screws on all 4 corners to add strength to the structure.     -   4. Put silicone to seal the drilled holes for main pipes to         avoid moisture.     -   5. Inspect the work for defect. The final work shall look like         FIG. 4.

After that, put fiber glass heat insulator or glass wool insulator 44 with 2 inches thickness, insulator density 24 kg/m³ with aluminum foil on 1 side, and line the fiber glass insulator on each side that may not be possible until it is completely covered. The side with aluminum foil shall be on the lower side of the PV module. Finally, install an aluminum cover door 48 at the lowest section. Before fastening with screw, seal all 4 sides with silicone to prevent moisture. The components are shown in FIG. 5 and the completely assembled version is shown in FIG. 6.

While this invention has been described as having an exemplary design, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains. 

1. A solar cell and water heater assembly for coupling to a pipe with a fluid therein comprising: a transparent plate used as base plate; a solar cell secured to the transparent plate; a heat collecting metal plate that is made of heat conductive metal coated with an electrical insulator, the electrical insulator configured to protect from short circuit and corrosion; a first layer of polymer glue which attaches the transparent plate and the heat collecting metal plate; a fastening plate which includes a clamping means for holding the pipe, the fastening plate being made of a heat-conductive material; and a second layer of polymer glue which attaches the combination of the heat collecting plate and the electrical insulator to the fastening plate so that solar heat can be transferred to the fluid in the heat conductive pipe.
 2. A solar cell and water heater assembly of claim 1, wherein the first and second layer of polymer glue are made of Ethylene Vinyl Acetate.
 3. A solar cell and water heater assembly of claim 1, wherein the heat collecting metal plate being coated with a layer of electrical insulator that is made of EVA (Ethylene Vinyl Acetate) polymer glue.
 4. A solar cell and water heater assembly of claim 1, wherein the electrical insulator made of Unitane.
 5. A solar cell and water heater assembly of claim 1, wherein the fastening plate is a flat plate and the clamping means being fixed approximately in the middle of the flat plate and approximately perpendicular to the flat plate.
 6. A solar cell and water heater assembly of claim 5, wherein the fastening plate further includes a first securing member positioned at a first end of the fastening plate and a second securing member positioned at a second end of the fastening plate, the second securing member being configured to cooperate with a first securing member of an adjacent fastening plate to secure the adjacent fastening plate to the fastening plate.
 7. A solar cell and water heater assembly of claim 6, wherein said first securing member is a notched niche and the second securing member is an edge end.
 8. A solar cell and water heater assembly of claim 1, wherein said clamping means includes a straight rail with one of a “U” shape cross-section and a semicircle shape cross-section, the cross-section extending in an approximately perpendicular direction to a plane of the fastening plate.
 9. A PVT collector comprising: an installation frame having a top, a middle, and a bottom portion; a light receptor glass plate installed on the top portion of the installation frame to create a green house effect; a solar cell and water heater plate assembly installed at the middle portion of the frame, the solar cell and water heater plate assembly configured to convert solar energy into electrical and heat energy; a heat insulator installed at the bottom portion of the frame; and a cover plate secured to the bottom portion to seal against moisture, wherein the solar cell and water heater plate assembly includes a transparent plate used as base plate; a solar cell secured to the transparent plate; a heat collecting metal plate that is made of heat conductive metal coated with an electrical insulator, the electrical insulator configured to protect from short circuit and corrosion; a first layer of polymer glue which attaches the transparent plate and the heat collecting metal plate; a fastening plate which includes a clamping means for holding the pipe, the fastening plate being made of a heat-conductive material; and a second layer of polymer glue which attaches the combination of the heat collecting plate and the electrical insulator to the fastening plate so that solar heat can be transferred to the fluid in the heat conductive pipe.
 10. The photovoltaic thermal collector of claim 9, wherein the heat collecting metal plate is coated with an electrical insulator made of a polyurethane.
 11. The photovoltaic thermal collector of claim 9, wherein the first and second layer of polymer glue are made of Ethylene Vinyl Acetate.
 12. A photovoltaic thermal collector of claim 9, wherein the fastening plate is a flat plate and the clamping means being fixed approximately in the middle of the flat plate and approximately perpendicular to the flat plate.
 13. A photovoltaic thermal collector of claim 12, wherein the fastening plate further includes a first securing member positioned at a first end of the fastening plate and a second securing member positioned at a second end of the fastening plate, the second securing member being configured to cooperate with a first securing member of an adjacent fastening plate to secure the adjacent fastening plate to the fastening plate.
 14. A photovoltaic thermal collector of claim 12, wherein said first securing member is a notched niche and the second securing member is an edge end.
 15. A photovoltaic thermal collector of claim 9, wherein said clamping means includes a straight rail with one of a “U” shape cross-section and a semicircle shape cross-section, the cross-section extending in an approximately perpendicular direction to a plane of the fastening plate.
 16. A PVT collector comprising: a frame; a fluid carrying conduit passing from an exterior of the frame into an interior of the frame and again to the exterior of the frame; and a solar cell and water heater plate assembly coupled to the frame, the solar cell and water heater plate assembly including a transparent base plate; a solar cell secured to the transparent base plate; a heat collecting plate positioned proximate the solar cell; a first layer of a polymer securing material which attaches the transparent base plate and the heat collecting metal plate; a fastening plate which includes a first portion that engages the fluid carrying conduit within the interior of the frame couple the fluid carrying conduit to the fastening plate; and a second layer of polymer securing material which attaches the heat collecting plate to the fastening plate so that during operation solar heat is transferred from the heat collecting plate to a fluid in the fluid carrying conduit.
 17. The PVT collector of claim 16, wherein the first portion of the fastening plate is generally shaped to contact a first exterior side of the fluid carrying conduit and a second exterior side of the fluid carrying conduit.
 18. The PVT collector of claim 17, wherein the first portion has one of a generally U-shaped and a generally semicircular shaped cross-section and wherein the transparent base plate, the heat collecting plate, and the fastening plate are each flat plates.
 19. The PVT collector of claim 16, wherein the first layer of polymer securing material and the second layer of polymer securing material each includes Ethylene Vinyl Acetate.
 20. The PVT collector of claim 19, wherein heat collecting plate is a metal plate which is coated on at least a first side with a polyurethane electrical insulator. 